“Turnbull has also shortened dramatically to be the leader of the Coalition at the next election.

“Prior to the call of the challenge Turnbull was $4.25 with CrownBet to be the Coalition Leader at the Next Election, but after today’s announcement he has shortened dramatically into $1.14.”

The boys at sportsbet.com.au have Turnbull a slightly juicier $1.10 to win the ballot, with Tony at a shorter $6 to continue in the roll.

Turnbull’s decision to challenge Abbott for the Liberal leadership has seen the Coalition shorten from $1.73 into $1.50 with the bookie to win the next Federal Election, while Labor has gone from $2.15 out to $2.65.

The boys at WilliamHill.com.au struck early, with Labor leader Bill Shorten going ahead of Abbott to become Prime Minister at the next election.

“As the Canberra rumour mill goes in to overdrive, Abbott has drifted in betting and is now rated the $4.25 outsider against Shorten ($2.65) and Malcolm Turnbull (3.20) to still be Prime Minister after the next election,” the bookie’s Tim Ashworth said.

“Bill Shorten shortening was naturally going to happen off the back of this, but to now have his Liberal colleague in Malcolm Turnbull ahead of him in betting paints a pretty bleak future for Abbott.”

Turnbull announced the decision to challenge Abbott this afternoon, launching a stinging attack on the Prime Minister.

“We need advocacy, not slogans,” he said.

“We need to respect the intelligence of the Australian people.

“There must be an end to the policy on the run and ‘captain’s calls’.

We need an open government.

“The big economic changes that we’re all living through here and around the world offer enormous challenges and enormous opportunities.

“And we need a different style of leadership.

“We need a style of leadership that explains those challenges and opportunities, explains the challenges and how to seize the opportunities.

“A style of leadership that respects the people’s intelligence, that explains these complex issues and then sets out the course of action we believe we should take and makes a case for it.

““The only way we can ensure that we remain a high wage, generous social welfare net, first world society is if we have outstanding economic leadership, if we have strong business confidence.

“That is what we in the Liberal Party are bound to deliver and it’s what I am committed to deliver if the party room gives me their support as leader of the party.

But Abbott, who said the ballot would be tonight, is confident he can hold on to his job.

“The Prime Ministership of this country is not a prize or a plaything to be demanded,” Mr Abbott said.

“It should be something which is earned by a vote of the Australian people.

“I will be a candidate and I expect to win.

“I have been heartened by the messages of support flooding into Liberal MPs’ offices this evening saying most emphatically, ‘we are not the Labor Party’.

“This country needs strong and stable government and that means avoiding, at all costs, Labor’s revolving-door prime ministership.

“Since coming to Government, our team has stopped the boats, improved the budget, cut taxes and increased jobs.

“We have laid the foundation for a better deal for families and for small business.

“You can trust me to deliver a stronger economy and a safer community.”

“Obviously, I am dismayed by the destabilisation that’s been taking place now for many, many months and I do say to my fellow Liberals that the destabilisation just has to stop.

“I firmly believe that our party is better than this, that our Government is better than this and, by God, that our country is so much better than this.”

The announcement of a leadership challenge has caused a bounce for the Liberals in the seat of Canning with Sportsbet.com.au, with Liberal candidate Andrew Hastie shortening from $1.27 into $1.20 following today’s announcement while Labor’s Matt Keogh has drifted back out to $4.

What is not certain is the final margin, with Sportsbet pricing a 10.01-12 per cent swing towards Labor at $2.50, a result which would create headaches for the Liberals.

Next in line is an 8.01-10 per cent swing at $3, with a more than 12 per cent swing, which would send the seat Labor’s way, priced at $3.60.

An unlikely swing towards the Liberals in Canning is priced at $41.

“Canning is expected to go down to the wire and while punters still think the Liberal party will win, the final margin is anyone’s guess with a large swing looking very likely,” sportsbet.com.au’s Ben Bulmer said.

Despite the talk, Ashworth said any change was unlikely to alter the result in the Canning By-Election with Hastie remaining the firm $1.28 favourite.